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A190474
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Numbers with prime factorization pqr^2s^6.
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2
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20160, 31680, 33600, 37440, 44352, 47040, 48960, 52416, 52800, 54720, 62400, 66240, 68544, 76608, 81600, 82368, 83520, 89280, 91200, 92736, 102060, 103488, 106560, 107712, 110400, 116160, 116928, 118080, 120384, 122304, 123200, 123840
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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f[n_]:=Sort[Last/@FactorInteger[n]]=={1, 1, 2, 6}; Select[Range[300000], f]
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PROG
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(PARI) list(lim)=my(v=List(), t1, t2, t3); forprime(p=2, sqrtnint(lim\60, 6), t1=p^6; forprime(q=2, sqrtint(lim\(6*t1)), if(q==p, next); t2=q^2*t1; forprime(r=2, lim\(2*t2), if(r==p || r==q, next); t3=r*t2; forprime(s=2, lim\t3, if(s==p || s==q || s==r, next); listput(v, t3*s))))); Set(v) \\ Charles R Greathouse IV, Aug 25 2016
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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